selling short

i have a question for my trader friends. what do you think of the daily volume on a stock is traded short. how often does it happen? yahoo shows a small percentage of the float as shorted stocks, but those are prolly long term investment numbers and its probable that shorting long term isnt as common as in intraday trading. also considering you can only short on an uptick, this might play a role. so how often do you short out of your total day trades and what percentage of the daily volume you think is shorted?

I have no idea what percent is shorted but can tell you here that in our office most trades trade long and short.
most will exit their long position and then look to scaled in a short position.
The traders here lot to short a stock that may of run long 6-8percent and look for a short of 1-3percent bases.
The traders also usually trade the same stocks and are familiar with the stock and it's daily volume, beta, news etc.

Percent wise 30-50percent of the trades in this office are shorts on a daily bases. We also have option straddles in place for most of the stock for security and additional revenue.